Two 'gay' male penguins have hatched an egg and are rearing the adopted chick.
The birds, at Bremerhaven Zoo in northern Germany, were given an egg rejected by its biological parents.
Named 'Z' and 'Vielpunkt', the penguins became famous when they refused to separate or to mate with females.
Joachim Schoene, a zoo vet, said; 'Another pair abandoned an egg by pushing it out of their nest and so we placed it in the care of the homosexual penguins.
Daddy's chick: The baby penguin in its cave at the Bremerhaven Zoo in northern Germany. It has been adopted by two gay - and proud - male penguins
'They accepted the egg immediately and took turns in incubating it with their body heat. They did this for 35 days and the baby was born on April 25.
'It is in a little cave in the enclosure which is fiercely guarded by one or the other at all times so we don't know yet if we have a little boy penguin or a little girl one.'
The two daddies feed their offspring with fish mash that they chew up and regurgitate into its ever-open beak.
Sorry, not allowed: Humboldt penguins Z and Vielpunkt stand guard at the entrance to the cave. They have protected their new chick so fiercely that zoo officials have not even been able to ascertain if the chick is a male or female yet
Mr Schoene added: 'In eight weeks the baby will have its downy fur and be able to be removed to move about the colony.'
Bremerhaven Zoo in northern Germany made headlines in 2005 as it investigated homosexual traits in penguins.
Gay rights activists were outraged after the zoo flew in female penguins to try to get them to reproduce with three pairs of male penguins who had been seen trying to mate with one another and hatch chicks from stones.
But now the zoo has relented, leaving the six gay penguins to live happily with their chosen mates - Z and Vielpunkt among them.
My two dads: Gay penguins become parents | Mail Online